/* -*- mode: C -*-  */
/* 
   IGraph library.
   Copyright (C) 2006-2012  Gabor Csardi <csardi.gabor@gmail.com>
   334 Harvard st, Cambridge MA, 02139 USA
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc.,  51 Franklin Street, Fifth Floor, Boston, MA 
   02110-1301 USA

*/

#include <igraph.h>

int main() {
  
  igraph_t g;
  igraph_real_t res;

  /* Trivial cases */

  igraph_ring(&g, 100, IGRAPH_UNDIRECTED, 0, 0);
  igraph_transitivity_undirected(&g, &res, IGRAPH_TRANSITIVITY_NAN);
  igraph_destroy(&g);

  if (res != 0) {
    return 1;
  }

  igraph_full(&g, 20, IGRAPH_UNDIRECTED, IGRAPH_NO_LOOPS);
  igraph_transitivity_undirected(&g, &res, IGRAPH_TRANSITIVITY_NAN);
  igraph_destroy(&g);
  
  if (res != 1) {
    return 2;
  }

  /* Degenerate cases */
  igraph_small(&g, 0, IGRAPH_UNDIRECTED,
		  0,  1,  2,  3,  4,  5, -1);
  igraph_transitivity_undirected(&g, &res, IGRAPH_TRANSITIVITY_NAN);
  /* res should be NaN here, any comparison must return false */
  if (res == 0 || res > 0 || res < 0) {
	return 4;
  }
  igraph_transitivity_undirected(&g, &res, IGRAPH_TRANSITIVITY_ZERO);
  /* res should be zero here */
  if (res) {
	return 5;
  }
  igraph_destroy(&g);

  /* Zachary Karate club */

  igraph_small(&g, 0, IGRAPH_UNDIRECTED, 
	       0,  1,  0,  2,  0,  3,  0,  4,  0,  5,
	       0,  6,  0,  7,  0,  8,  0, 10,  0, 11,
	       0, 12,  0, 13,  0, 17,  0, 19,  0, 21,
	       0, 31,  1,  2,  1,  3,  1,  7,  1, 13,
	       1, 17,  1, 19,  1, 21,  1, 30,  2,  3,
	       2,  7,  2,  8,  2,  9,  2, 13,  2, 27,
	       2, 28,  2, 32,  3,  7,  3, 12,  3, 13,
	       4,  6,  4, 10,  5,  6,  5, 10,  5, 16,
	       6, 16,  8, 30,  8, 32,  8, 33,  9, 33,
	       13, 33, 14, 32, 14, 33, 15, 32, 15, 33,
	       18, 32, 18, 33, 19, 33, 20, 32, 20, 33,
	       22, 32, 22, 33, 23, 25, 23, 27, 23, 29,
	       23, 32, 23, 33, 24, 25, 24, 27, 24, 31,
	       25, 31, 26, 29, 26, 33, 27, 33, 28, 31,
	       28, 33, 29, 32, 29, 33, 30, 32, 30, 33,
	       31, 32, 31, 33, 32, 33,
	       -1);  
  
  igraph_transitivity_undirected(&g, &res, IGRAPH_TRANSITIVITY_NAN);
  igraph_destroy(&g);
  
  if (res != 0.2556818181818181767717) {
    fprintf(stderr, "%f != %f\n", res, 0.2556818181818181767717);
    return 3;
  }

  return 0;
}
